<template>
  <ul :class="simpleWrapClasses" :style="styles" v-if="simple">
    <li :title="t('i.page.prev')" :class="prevClasses" @click="prev">
      <!-- <a><i class="ivu-icon ivu-icon-ios-arrow-left"></i></a> -->
      <a class="pager-prev-next-text">{{t('i.page.prev')}}</a>
    </li>
    <div :class="simplePagerClasses" :title="currentPage + '/' + allPages">
      <input type="text" :value="currentPage" @keydown="keyDown" @keyup="keyUp" @change="keyUp">
      <span>/</span> {{ allPages }}
    </div>
    <li :title="t('i.page.next')" :class="nextClasses" @click="next">
      <!-- <a><i class="ivu-icon ivu-icon-ios-arrow-right"></i></a> -->
      <a class="pager-prev-next-text">{{t('i.page.next')}}</a>
    </li>
  </ul>
  <ul :class="wrapClasses" :style="styles" v-else>
    <span :class="[prefixCls + '-total']" v-if="showTotal">
            <slot>{{ t('i.page.total') }} {{ total }} <template v-if="total <= 1">{{ t('i.page.item') }}</template><template v-else>{{ t('i.page.items') }}</template></slot>
        </span>
    <li :title="t('i.page.prev')" :class="prevClasses" @click="prev">
      <!-- <a><i class="ivu-icon ivu-icon-ios-arrow-left"></i></a> -->
      <a class="pager-prev-next-text">{{t('i.page.prev')}}</a>
    </li>
    <li title="1" :class="firstPageClasses" @click="changePage(1)"><a>1</a></li>
    <li :title="t('i.page.prev5')" v-if="currentPage - 3 > 1" :class="[prefixCls + '-item-jump-prev']" @click="fastPrev"><a><i class="ivu-icon ivu-icon-ios-arrow-left"></i></a></li>
    <li :title="currentPage - 2" v-if="currentPage - 2 > 1" :class="[prefixCls + '-item']" @click="changePage(currentPage - 2)"><a>{{ currentPage - 2 }}</a></li>
    <li :title="currentPage - 1" v-if="currentPage - 1 > 1" :class="[prefixCls + '-item']" @click="changePage(currentPage - 1)"><a>{{ currentPage - 1 }}</a></li>
    <li :title="currentPage" v-if="currentPage != 1 && currentPage != allPages" :class="[prefixCls + '-item',prefixCls + '-item-active']"><a>{{ currentPage }}</a></li>
    <li :title="currentPage + 1" v-if="currentPage + 1 < allPages" :class="[prefixCls + '-item']" @click="changePage(currentPage + 1)"><a>{{ currentPage + 1 }}</a></li>
    <li :title="currentPage + 2" v-if="currentPage + 2 < allPages" :class="[prefixCls + '-item']" @click="changePage(currentPage + 2)"><a>{{ currentPage + 2 }}</a></li>
    <li :title="t('i.page.next5')" v-if="currentPage + 3 < allPages" :class="[prefixCls + '-item-jump-next']" @click="fastNext"><a><i class="ivu-icon ivu-icon-ios-arrow-right"></i></a></li>
    <li :title="allPages" v-if="allPages > 1" :class="lastPageClasses" @click="changePage(allPages)"><a>{{ allPages }}</a></li>
    <li :title="t('i.page.next')" :class="nextClasses" @click="next">
      <!-- <a><i class="ivu-icon ivu-icon-ios-arrow-right"></i></a> -->
      <a class="pager-prev-next-text">{{t('i.page.next')}}</a>
    </li>
    <Options :show-sizer="showSizer" :page-size="currentPageSize" :page-size-opts="pageSizeOpts" :placement="placement" :show-elevator="showElevator" :_current.once="currentPage" :current="currentPage" :all-pages="allPages" :is-small="isSmall" @on-size="onSize" @on-page="onPage">
    </Options>
  </ul>
</template>
<script>
import {
  oneOf
} from '../../utils/assist';
import Options from './options.vue';
import Locale from '../../mixins/locale';

const prefixCls = 'ivu-page';

export default {
  name: 'Page',
  mixins: [Locale],
  components: {
    Options
  },
  props: {
    current: {
      type: Number,
      default: 1
    },
    total: {
      type: Number,
      default: 0
    },
    pageSize: {
      type: Number,
      default: 10
    },
    pageSizeOpts: {
      type: Array,
      default () {
        return [10, 20, 30, 40];
      }
    },
    placement: {
      validator(value) {
        return oneOf(value, ['top', 'bottom']);
      },
      default: 'bottom'
    },
    size: {
      validator(value) {
        return oneOf(value, ['small']);
      }
    },
    simple: {
      type: Boolean,
      default: false
    },
    showTotal: {
      type: Boolean,
      default: false
    },
    showElevator: {
      type: Boolean,
      default: false
    },
    showSizer: {
      type: Boolean,
      default: false
    },
    className: {
      type: String
    },
    styles: {
      type: Object
    }
  },
  data() {
    return {
      prefixCls: prefixCls,
      currentPage: this.current,
      currentPageSize: this.pageSize
    };
  },
  watch: {
    current(val) {
      this.currentPage = val;
    },
    pageSize(val) {
      this.currentPageSize = val;
    }
  },
  computed: {
    isSmall() {
      return !!this.size;
    },
    allPages() {
      const allPage = Math.ceil(this.total / this.currentPageSize);
      return (allPage === 0) ? 1 : allPage;
    },
    simpleWrapClasses() {
      return [
        `${prefixCls}`,
        `${prefixCls}-simple`, {
          [`${this.className}`]: !!this.className
        }
      ];
    },
    simplePagerClasses() {
      return `${prefixCls}-simple-pager`;
    },
    wrapClasses() {
      return [
        `${prefixCls}`, {
          [`${this.className}`]: !!this.className,
          'mini': !!this.size
        }
      ];
    },
    prevClasses() {
      return [
        `${prefixCls}-prev`, {
          [`${prefixCls}-disabled`]: this.currentPage === 1
        }
      ];
    },
    nextClasses() {
      return [
        `${prefixCls}-next`, {
          [`${prefixCls}-disabled`]: this.currentPage === this.allPages
        }
      ];
    },
    firstPageClasses() {
      return [
        `${prefixCls}-item`, {
          [`${prefixCls}-item-active`]: this.currentPage === 1
        }
      ];
    },
    lastPageClasses() {
      return [
        `${prefixCls}-item`, {
          [`${prefixCls}-item-active`]: this.currentPage === this.allPages
        }
      ];
    }
  },
  methods: {
    changePage(page) {
      if (this.currentPage != page) {
        this.currentPage = page;
        this.$emit('on-change', page);
      }
    },
    prev() {
      const current = this.currentPage;
      if (current <= 1) {
        return false;
      }
      this.changePage(current - 1);
    },
    next() {
      const current = this.currentPage;
      if (current >= this.allPages) {
        return false;
      }
      this.changePage(current + 1);
    },
    fastPrev() {
      const page = this.currentPage - 5;
      if (page > 0) {
        this.changePage(page);
      } else {
        this.changePage(1);
      }
    },
    fastNext() {
      const page = this.currentPage + 5;
      if (page > this.allPages) {
        this.changePage(this.allPages);
      } else {
        this.changePage(page);
      }
    },
    onSize(pageSize) {
      this.currentPageSize = pageSize;
      this.changePage(1);
      this.$emit('on-page-size-change', pageSize);
    },
    onPage(page) {
      this.changePage(page);
    },
    keyDown(e) {
      const key = e.keyCode;
      const condition = (key >= 48 && key <= 57) || key == 8 || key == 37 || key == 39;

      if (!condition) {
        e.preventDefault();
      }
    },
    keyUp(e) {
      const key = e.keyCode;
      const val = parseInt(e.target.value);

      if (key === 38) {
        this.prev();
      } else if (key === 40) {
        this.next();
      } else if (key == 13) {
        let page = 1;

        if (val > this.allPages) {
          page = this.allPages;
        } else if (val <= 0) {
          page = 1;
        } else {
          page = val;
        }

        e.target.value = page;
        this.changePage(page);
      }
    }
  }
};
</script>
